This invention relates to a low noise block down-converter for satellite broadcast receivers and, more particularly, a low-cost, low noise block down-converter having a self-oscillating mixer for use in direct-to-home satellite receivers.
In the past few years the demand for more diversified satellite services has continued to grow. For example, there has been widespread recent interest in new media services such as integrated services of digital broadcasting (ISDB) and digital high-definition TV (HDTV). Among the various types of satellite communication systems for distributing these and the more conventional satellite services, direct broadcasting satellite (DBS) has become a major system. For example, as of the end of 1993, the broadcasting satellite system ASTRA 1A, 1B and 1C has reached over forty-five million homes across Europe. Over ten million of those homes own direct-to-home (DTH) satellite receiver equipment. Moreover, in Asia, North and South America, DTH satellite broadcasting is also emerging as a strong contender for market share presently possessed by the more conventional "cable" TV service.
In DBS, the low noise block (LNB) down-converter that amplifies and converts the extremely weak microwave signals down to UHF signals is generally considered one of the most critical components in the satellite receiver system. Because of recent advances in III-V compound semiconductor electronics, especially the development and commercialization of high electron mobility transistors (HEMTs), it is now possible to make high-quality, low noise block down-converters available to the mass market. However, there is still a need for improving the manufacturing yield and reliability of such down-converters, as well as reducing their cost. In particular, there is a need for reducing the number of components in the LNB down-converter in order to provide high performance at low cost.
In light of the above, it would be desirable to be able to provide a low noise block down-converter with improved manufacturing yield and reliability for use in a receiver in a satellite broadcasting system.
It would also be desirable to be able to provide a low noise block down-converter for use in a receiver in a satellite broadcasting system that can be manufactured at lower cost.
It would further be desirable to be able to provide a low noise block down-converter for use in a receiver in a satellite broadcasting system that can provide high performance for low cost.